Gumming device

ABSTRACT

The envelope machine includes apparatus to fold the side flaps of the envelope blank and convey the envelope blank to a gumming device. The envelope blank is engaged by vacuum on a bottom flap folding cylinder positioned below a gumming roller. The gumming roller has applicator segments with arcuate surfaces that are arranged to apply strips of gum to the side flaps of the envelope blank as it is supported on the ends of radially extending bristles on the blank support brush portion of the bottom flap folding cylinder. The envelope blank with the gum applied to the side flaps is conveyed between the bottom flap folding cylinder and a transfer cylinder where the bottom flap is folded over the side flaps. Thereafter the transfer cylinder conveys the envelope to a seal flap folding device where the seal flap is folded over the bottom flap. From the seal flap folding device the finished envelope is conveyed to a spiral delivery disc. The bristles on the brush portion of the bottom flap folding cylinder terminate in an arcuate semi-circular configuration that conforms to the diameter of the bottom flap folding cylinder.

United States Patent [191 Helm [ June 18, 1974 GUMMJNG DEVICE [75] Inventor: Herbert W. Helm, Hollidaysburg,

[73] Assignee: F. L. Smith Machine Company, Inc.,

' Duncansville, Pa.

[22] Filed: June 29, 1972 v 21 Appl. No.: 267,530

[52] US. Cl 118/50, 118/249 [51] Int. Cl. B05c 1/02 [58] Field of Search 118/249, 250, 224, 50, 118/248 [56] References Cited UNITED STATES PATENTS 2,007,882 7/1935 Shields ll8/249 X 2,033,849 .3/1936 Mudd 118/249 X 2,821,161 l/l958 Winkler et a1. 1l8/249 X Wakefield 1 18/249 Primary Examiner-John P. McIntosh Attorney, Agent, or FirmStanley J. Price, Jr.

[5 7] ABSTRACT The envelope machine includes apparatus to fold the side flaps of the envelope blank and convey the envelope blank to a gumming device. The envelope blank is engaged by vacuum on a bottom flap folding cylinder positioned below a gumming roller. The gumming roller has applicator segments with arcuate surfaces that are arranged to apply strips of gum to the side flaps of the envelope blank as it is supported on the ends of radially extending bristles on the blank support brush portion of the bottom flap folding cylinder.

7 The envelope blank with the gum applied to the side flaps is conveyed between the bottom flap folding cylinder and a transfer cylinder where the bottom flap is folded over the side flaps. Thereafter the transfer cylinder conveys the envelope to a seal flap folding device where the seal flap is folded over the bottom flap. From the seal flap folding device the finished envelope is conveyed to a spiral delivery disc. The bristles on the brush portion of the bottom flap folding cylinder terminate in an arcuate semi-circular configuration that conforms to the diameter of the bottom flap folding cylinder.

8 Claims, 4 Drawing Figures 1 GUMMING DEVICE 1. Field of the Invention This invention relates to a gumming device for envelope making machines and more particularly to the backing roller for the gum applicator.

2. Description of the Prior Art Gumming devices for envelope making machines operate continuously in cooperation with other elements of the machine. The conventional gum applicators contact the envelope blank as the blank is conveyed through the envelope machine thus transferring a strip of gum from an applicator to the envelope blank. The applicator is in the form of a roller having, in certain instances, applicator segments and a cooperating pressure roller or plate. The envelope blanks are fed in timed relation between the applicator and the pressure roller. Under ordinary operating conditions a blank is positioned between the applicator and the pressure roller when the applicator moves into overlying relation with the backing roller so that the gum on the surface of the applicator is transferred to the envelope blank. Where the stream of envelope blanks is interrupted and an envelope blank is not present between the applicator and the backing roller, under ordinary circumstances, the gum would be transferred tothe backing roller. When operation of the envelope machine is resumed and a stream of envelope blanks are fed between the applicator and pressure roller, the body portion of certain of the envelope blanks would adhere to the backing roll and interfere with the operation of the machine.

Several solutions to this problem have been suggested by the prior art. For example, U.S. Pat. No. 1,939,359 provides a planar guide plate backing member for a rotating disc type applicator with the envelope blank side flap passing between the planar guide plate backing member and the disc applicator. The plate has an elongated recess opposite the edge of the disc that is arranged to prevent adhesive from being transferred to the guide plate in the absence of a blank or during the interval between successive blanks.

U.S. Pat. No. 1,961,162 has a gum supply roll spaced from a shaft on which a pair of gum transferring blades are mounted. The shaft on rotation moves the gum transferring blades successively against the gum supply roll and the envelope blank supported on a back up feed roll. A trip mechanism is provided to shift the axis of rotation of the shaft supporting the gum transferring blades when an envelope blank is missing. The gum applying blades thus escape engagement with the gum applying roll and with the backing roll.

U.S. Pat. No. 2,1 1 1,317 includes gum removing blades abutting the back up cylinder and an engaging roll that is partially immersed in water. The engaging roll moistens the gum not removed by the blade and other blades are positioned to remove the moistened gum.

In U.S. Pat. No. 3,019,761 the back up or feed cylinder has arcuate recesses therein that cooperate with the gum transfer blades so that when a blank is missing the gum transferring blades are coicidental with the recesses and the film of gum on the transfer blades is not transferred to the back up cylinder. With this latter arrangement, since the recesses are coincidental with the gum transferring blades, it is necessary when changing over from one sized envelope blank to another to adjust both the transfer blades and the portions of the feed or back up cylinder having the arcuate recesses so that both the recesses and the gum transferring blades are coincidental with each other for the different sized envelope blank. There is a need for gumming apparatus that does not require the time consuming adjustment of the recessed portions of the back up roller change over from one sized envelope to another.

SUMMARY OF THE INVENTION This invention relates to an improved gumming device that includes a rotatable gum applicator positioned adjacent to a backing cylinder. The gum applicator is arranged to transfer a film of gum to a portion of a blank as the blank is conveyed between the rotatable gum applicator and the backing cylinder. The backing cylinder has an arcuate brush portion with the bristles extending radially relative to the backing cylinder. The backing cylinder is arranged to support the blank on the ends of the bristles while the gum applicator transfers gum to a surface of the blank.

With this arrangement the gum applicator transfers only a portion of the film of gum to the ends of the underlying bristles when a blank is not positioned therebetween and blanks subsequently fed between the applicator and the backing cylinder do not adhere to the backing cylinder and interrupt operation of the gumming device.

Also, because the arcuate brush portion extends along a substantial length of the backing cylinder, adjustment of the backing cylinder is not required when the gum applicator is adjusted for different sized blanks.

Accordingly, the principal object of this invention is to provide a backing cylinder for a gumming device in which a blank will not be adhesively engaged thereto when gum is transferred to the backing cylinder.

Another object of this invention is to provide a backing cylinder for a gumming device that does not require adjustment for different sized blanks.

These and other objects and advantages of this invention will be more completely disclosed and described in the following specification, the accompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 3 is a view in section taken along the Line 111- III of FIG. 2, illustrating in section the arcuate brush support and the vacuum bar.

FIG. 4 is a plan view of an envelope blank with the side flaps folded and the strips of gum applied thereto.

DESCRIP'T ION OF THE PREFERRED EMBODIMENT FIG. 4 illustrates an envelope blank generally designated by the numeral 14 having a body portion 16, a bottom flap 18, a seal flap 20 and a pair of side flaps 22 and 24. The envelope blank 14 is scored longitudinally along the side flap score lines 26, 28 and trans versely along a bottom flap score line 30 and seal flap score line 32.

The portion of the envelope machine generally designated by the numeral in FIG. 1 includes a pair of plowshares 12.

The side flaps 22 and 24 of envelope blank 14, as it is conveyed through the plowshares 12, are folded along the score lines 26 and 28. The envelope blanks are thereafter conveyed by rolls 36 and 38 to side flap gummer apparatus generally designated by the numeral 40. A guide plate 42 directs the envelope blanks between a bottom flap folding cylinder generally designated by the numeral 44 and a gum applicator roll 46. The bottom flap folding cylinder 44 has a longitudinal vacuum bar 48 that engages the envelope body portion 16 adjacent the bottom flap score line 30. Positioned adjacent the seal flap fold cylinder 44 is a transfer cylinder 50 with other suitable vacuum devices (not shown). As later described, the bottom flap 18 is folded along the score line 30 by cylinders 44 and 50. Rotation of the bottom flap folding cylinder 44 conveys the envelope blank to the adjacent transfer cylinder 50. The bottom flap folding cylinder has an arcuate semicylindrical brush portion generally designated by the numeral 52 that supports the envelope blank body portion 16 as strips of gum are applied to the side flaps 22 and 24.

A reservoir 54 is positioned above the gum applicator roll 46 and is supplied with liquid adhesive or gum from container 58 positioned thereabove. A roller 60 receives a supply of gum from reservoir 54 and transfers a film of the gum to roller 62. The roller 62 periodically contacts the segmented portions 64 of roller 46 and transfers the film of gum to the outer surfaces 68 of the respective segments 64. The roller 46 rotates in timed relation with the bottom flap folding cylinder 44 so that the surfaces 68 of segments 64 are in overlying relation with the side flaps 22 and 24 as the envelope blank is.

conveyed by the bottom flap folding cylinder 44. The surfaces 68 of the segments apply the film of gum in the form of strips 70 and 72 to the side flaps of the envelope 14 as is illustrated in FIG. 4. The envelope blank with the strips of gum 70 and 72 applied to the side flaps 22 and 24 is thereafter conveyed between the bottom flap folding cylinder and transfer cylinder 50 where the bottom flap 18 is folded along the source line 30 into overlying relation with the side flaps 22 and 24. The envelope 14 with the seal flap open is then engaged by means of suitable suction devices not illustrated on transfer cylinder 50 and conveyed to a seal flap folding device generally indicated by the numeral 74. The envelope blank is conveyed upwardly into a slotted trap 76 against a stop and folded along the seal flap score line 32 between roller 78 and delivery cylinder 80. The seal flap is folded over the bottom flap 18 to form a finished envelope. The delivery cylinder 80 then delivers the finished envelope to a spiral delivery disc 82 that has a plurality of arcuate slots 84 therein. The finished envelopes are thereafter transferred from the spiral delivery disc 82 to an endless conveyor belt 86. Guide plates 79 are positioned beneath the transfer cylinder 50 and the delivery cylinder 80 to support portions of the envelope blank. It should be understood the previously described rollers and cylinders are suitably supported in the machine frame and are drivingly connected to each other to rotate in timed relation and convey the envelope blanks and perform the envelope forming operations in desired sequence and register. The supports and drives are omitted to more clearly illustrate the invention.

Referring to FIGS. 2 and 3, the bottom flap folding cylinder 44 has a longitudinal recessed portion 88 in which the vacuum bar 48 is positioned. The vacuum bar 48 has a plurality of vacuum ports 90 along the periphery of the cylinder 44. The cylinder 44 has an arcu' ate recessed portion 92 and a threaded bore 94. A semi-cylindrical brush generally designated by the numeral 52 has an arcuate base portion 96 with substantially the same configuration as the external arcuate surface of recessed portion 92. A bolt 98 secures the brush 52 to the cylinder 44. The brush has a plurality of radially extending bristles 100 that form an external bristle surface 102 having substantially the same circumferential dimension as the cylinder 44. With this arrangement approximately one-half of the bottom flap folding cylinder has an external surface formed by the ends of the bristles 100 extending radially from the base 96.

The end portions of the bristles 100 are arranged to support the envelope blank body portion 16 as the gum applying segments 64 apply strips of gum 70 and 72 to the side flaps 22 and 24. When, because of failure of the envelope blank feeding mechanism or because the supply of envelope blanks is exhausted and no blank is available between the bottom flap folding cylinder 44 and the gum applying segments, the gum on the surface 68 of the gum applying segments 64 contacts only the end portions of the bristles 100 that underlie the surface 68 of the gum applying segments. With this arrangement, the backing roller for the gum applicator does not receive the entire continuous strip of gum that would ordinarily be applied to the seal flaps. Only the end portions of the bristles engage the adhesive film and minute amounts of adhesive are transferred to the ends of the bristles. The gum adhering to the ends of the bristles is quickly and effectively removed by the body portion of two or three envelope blanks as the supply of blanks is resumed. The blanks do not adhere to the brush and the slight amount of adhesive on the bristle tips or end portions does not interrupt the envelope forming operation.

The brush 52 is constructed with bristles preferably of a polymeric material such as nylon or the like, that have sufficient rigidity to support the envelope blank during the application of the strips of gum to the seal flaps. Since the brush 52 extends substantially the full length of the bottom flap cylinder 44, adjustments in the bottom flap folding cylinder for different sized blanks are no longer required. Although illustrated as a single brush, it should be understood that a plurality of brush segments may also be employed without departing from the herein described invention. Although the brush segment backing member has been described in reference to the backing roll for apparatus to apply gum to the side flaps of an envelope blank it is not intended to be limited to this specific application and has application as a backing member in any apparatus where gum is applied to the surface of a blank or sheet.

According to the provisions of the patent statutes, I have explained the principle, preferred construction and mode of operation of my invention and illustrated and described what I now consider to represent its best embodiment. It should be expressly understood, however, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated.

I claim:

1. A gumming device comprising,

a rotatable gum applicator having an arcuate outer surface adapted to receive a film of gum and transfer atleast a portion of the film of gum from the arcuate outer surface to a surface of a blank,

a backing member positioned adjacent to said gum applicator and arranged to support a surface of said blank as said film of gum is transferred to said blank,

said backing member including means to engage said blank to said backing member, and

said backing member having a support surface with a plurality of brush-like bristles extending toward said gum applicator.

2. A gumming device as set forth in claim 1 in which said support surface includes,

said plurality of brush-like bristles secured to said backing member with the brush bristle end portions positioned adjacent to said gum applicator as said film of gum is transferred to said blank.

3. A gumming device as set forth in claim 1 inwhich said backing member support surface includes,

said plurality of brush-like bristles having outwardly extending bristle end portions,

said backing memberarranged to support said blank on said bristle end portions as said film of gum is transferred'to said blank. 4. A gumming device as set forth in claim 1 in which said backing member includes,

a rotatable backing cylinder positioned adjacent to said gum applicator and arranged to rotate in timed relation thereto.

5. A gumming device as set forth in claim 4 in which said means to engage said blank to said backing cylinder includes,

an elongated vacuum bar extending longitudinally along the surface of said cylinder and arranged to engage a blank thereto by vacuum.

6. A gumming device as set forth in claim 5 in which said rotatable backing cylinder includes,

an arcuate recessed portion extending longitudinally through a substantial portion of said cylinder with an arcuate surface,

said plurality of brush-like bristlesforming a brush member with an arcuate base portion having substantially the same configuration as the arcuate surface of said recessed portion,

said brush member arcuate base portion secured to said cylinder recessed portion arcuate surface,

said plurality of brush-like bristles on said brush member extending radially relative to the axis of said cylinder and terminating in bristle end portions. 7

7. A gumming device as set forth in claim 6 in which,

said brush member extends longitudinally along a substantial portion of said rotatable backing cylinder. 

1. A gumming device comprising, a rotatable gum applicator having an arcuate outer surface adapted to receive a film of gum and transfer at least a portion of the film of gum from the arcuate outer surface to a surface of a blank, a backing member positioned adjacent to said gum applicator and arranged to support a surface of said blank as said film of gum is transferred to said blank, said backing member including means to engage said blank to said backing member, and said backing member having a support surface with a plurality of brush-like bristles extending toward said gum appliCator.
 2. A gumming device as set forth in claim 1 in which said support surface includes, said plurality of brush-like bristles secured to said backing member with the brush bristle end portions positioned adjacent to said gum applicator as said film of gum is transferred to said blank.
 3. A gumming device as set forth in claim 1 in which said backing member support surface includes, said plurality of brush-like bristles having outwardly extending bristle end portions, said backing member arranged to support said blank on said bristle end portions as said film of gum is transferred to said blank.
 4. A gumming device as set forth in claim 1 in which said backing member includes, a rotatable backing cylinder positioned adjacent to said gum applicator and arranged to rotate in timed relation thereto.
 5. A gumming device as set forth in claim 4 in which said means to engage said blank to said backing cylinder includes, an elongated vacuum bar extending longitudinally along the surface of said cylinder and arranged to engage a blank thereto by vacuum.
 6. A gumming device as set forth in claim 5 in which said rotatable backing cylinder includes, an arcuate recessed portion extending longitudinally through a substantial portion of said cylinder with an arcuate surface, said plurality of brush-like bristles forming a brush member with an arcuate base portion having substantially the same configuration as the arcuate surface of said recessed portion, said brush member arcuate base portion secured to said cylinder recessed portion arcuate surface, said plurality of brush-like bristles on said brush member extending radially relative to the axis of said cylinder and terminating in bristle end portions.
 7. A gumming device as set forth in claim 6 in which, said bristle end portions terminate in an arcuate surface having substantially the same diameter on said backing cylinder.
 8. A gumming device as set forth in claim 6 in which, said brush member extends longitudinally along a substantial portion of said rotatable backing cylinder. 